;;; trace.el --- tracing facility for Emacs Lisp functions;; Copyright (C) 1993 Free Software Foundation, Inc.;; Author: Hans Chalupsky <hans@cs.buffalo.edu>;; Created: 15 Dec 1992;; Keywords: tools, lisp;; This file is part of XEmacs.;; XEmacs is free software; you can redistribute it and/or modify it;; under the terms of the GNU General Public License as published by;; the Free Software Foundation; either version 2, or (at your option);; any later version.;; XEmacs is distributed in the hope that it will be useful, but;; WITHOUT ANY WARRANTY; without even the implied warranty of;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU;; General Public License for more details.;; You should have received a copy of the GNU General Public License;; along with XEmacs; see the file COPYING. If not, write to the Free;; Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA;; 02111-1307, USA.;;; Synched up with: FSF 19.34.;; LCD Archive Entry:;; trace|Hans Chalupsky|hans@cs.buffalo.edu|;; Tracing facility for Emacs Lisp functions|;; 1993/05/18 00:41:16|2.0|~/packages/trace.el.Z|;;; Commentary:;; Introduction:;; =============;; A simple trace package that utilizes advice.el. It generates trace ;; information in a Lisp-style fashion and inserts it into a trace output;; buffer. Tracing can be done in the background (or silently) so that;; generation of trace output won't interfere with what you are currently;; doing.;; How to get the latest trace.el:;; ===============================;; You can get the latest version of this file either via anonymous ftp from ;; ftp.cs.buffalo.edu (128.205.32.9) with pathname /pub/Emacs/trace.el,;; or send email to hans@cs.buffalo.edu and I'll mail it to you.;; Requirement:;; ============;; trace.el needs advice.el version 2.0 or later which you can get from the;; same place from where you got trace.el.;; Restrictions:;; =============;; - Traced subrs when called interactively will always show nil as the;; value of their arguments.;; - Only functions/macros/subrs that are called via their function cell will;; generate trace output, hence, you won't get trace output for:;; + Subrs called directly from other subrs/C-code;; + Compiled calls to subrs that have special byte-codes associated;; with them (e.g., car, cdr, ...);; + Macros that were expanded during compilation;; - All the restrictions that apply to advice.el;; Installation:;; =============;; Put this file together with advice.el (version 2.0 or later) somewhere;; into your Emacs `load-path', byte-compile it/them for efficiency, and;; put the following autoload declarations into your .emacs;;;; (autoload 'trace-function "trace" "Trace a function" t);; (autoload 'trace-function-background "trace" "Trace a function" t);;;; or explicitly load it with (require 'trace) or (load "trace").;; Comments, suggestions, bug reports;; ==================================;; are strongly appreciated, please email them to hans@cs.buffalo.edu.;; Usage:;; ======;; - To trace a function say `M-x trace-function' which will ask you for the;; name of the function/subr/macro to trace, as well as for the buffer;; into which trace output should go.;; - If you want to trace a function that switches buffers or does other;; display oriented stuff use `M-x trace-function-background' which will;; generate the trace output silently in the background without popping;; up windows and doing other irritating stuff.;; - To untrace a function say `M-x untrace-function'.;; - To untrace all currently traced functions say `M-x untrace-all'.;; Examples:;; =========;;;; (defun fact (n);; (if (= n 0) 1;; (* n (fact (1- n)))));; fact;; ;; (trace-function 'fact);; fact;;;; Now, evaluating this...;;;; (fact 4);; 24;;;; ...will generate the following in *trace-buffer*:;;;; 1 -> fact: n=4;; | 2 -> fact: n=3;; | | 3 -> fact: n=2;; | | | 4 -> fact: n=1;; | | | | 5 -> fact: n=0;; | | | | 5 <- fact: 1;; | | | 4 <- fact: 1;; | | 3 <- fact: 2;; | 2 <- fact: 6;; 1 <- fact: 24;;;;;; (defun ack (x y z);; (if (= x 0) ;; (+ y z);; (if (and (<= x 2) (= z 0)) ;; (1- x);; (if (and (> x 2) (= z 0)) ;; y;; (ack (1- x) y (ack x y (1- z)))))));; ack;;;; (trace-function 'ack);; ack;;;; Try this for some interesting trace output:;;;; (ack 3 3 1);; 27;;;; ;; The following does something similar to the functionality of the package;; log-message.el by Robert Potter, which is giving you a chance to look at;; messages that might have whizzed by too quickly (you won't see subr;; generated messages though):;;;; (trace-function-background 'message "*Message Log*");;; Change Log:;; Revision 2.0 1993/05/18 00:41:16 hans;; * Adapted for advice.el 2.0; it now also works;; for GNU Emacs-19 and XEmacs;; * Separate function `trace-function-background';; * Separate pieces of advice for foreground and background tracing;; * Less insane handling of interactive trace buffer specification;; * String arguments and values are now printed properly;;;; Revision 1.1 1992/12/15 22:45:15 hans;; * Created, first public release;;; Code:(require'advice);; XEmacs change (leave the version # in place)(defconsttrace-version"2.0");;;###autoload(defvartrace-buffer"*trace-output*""*Trace output will by default go to that buffer.");; Current level of traced function invocation:(defvartrace-level0);; Semi-cryptic name used for a piece of trace advice:(defvartrace-advice-name'trace-function\ );; Used to separate new trace output from previous traced runs:(defvartrace-separator(format"%s\n"(make-string70?=)))(defuntrace-entry-message(functionlevelargument-bindings);; Generates a string that describes that FUNCTION has been entered at;; trace LEVEL with ARGUMENT-BINDINGS.(format"%s%s%d -> %s: %s\n"(mapconcat'char-to-string(make-string(1-level)?|) " ") (if (> level 1) " " "") level function (mapconcat (function (lambda (binding) (concat (symbol-name (ad-arg-binding-field binding 'name)) "=" ;; do this so we'll see strings: (prin1-to-string (ad-arg-binding-field binding 'value))))) argument-bindings " ")))(defun trace-exit-message (function level value) ;; Generates a string that describes that FUNCTION has been exited at ;; trace LEVEL and that it returned VALUE. (format "%s%s%d <- %s: %s\n" (mapconcat 'char-to-string (make-string (1- level) ?|)" ")(if(>level1)" """)levelfunction;; do this so we'll see strings:(prin1-to-stringvalue)))(defuntrace-make-advice(functionbufferbackground);; Builds the piece of advice to be added to FUNCTION's advice info;; so that it will generate the proper trace output in BUFFER;; (quietly if BACKGROUND is t).(ad-make-advicetrace-advice-namenilt(cond(background(`(advicelambda()(let((trace-level(1+trace-level))(trace-buffer(get-buffer-create(,buffer))))(save-excursion(set-buffertrace-buffer)(goto-char(point-max));; Insert a separator from previous trace output:(if(=trace-level1)(inserttrace-separator))(insert(trace-entry-message'(,function)trace-levelad-arg-bindings)))ad-do-it(save-excursion(set-buffertrace-buffer)(goto-char(point-max))(insert(trace-exit-message'(,function)trace-levelad-return-value)))))))(t(`(advicelambda()(let((trace-level(1+trace-level))(trace-buffer(get-buffer-create(,buffer))))(pop-to-buffertrace-buffer)(goto-char(point-max));; Insert a separator from previous trace output:(if(=trace-level1)(inserttrace-separator))(insert(trace-entry-message'(,function)trace-levelad-arg-bindings))ad-do-it(pop-to-buffertrace-buffer)(goto-char(point-max))(insert(trace-exit-message'(,function)trace-levelad-return-value)))))))))(defuntrace-function-internal(functionbufferbackground);; Adds trace advice for FUNCTION and activates it.(ad-add-advicefunction(trace-make-advicefunction(orbuffertrace-buffer)background)'around'last)(ad-activatefunctionnil))(defuntrace-is-traced(function)(ad-find-advicefunction'aroundtrace-advice-name));; shamelessly stolen from find-func(defuntrace-function-read(prompt)"Read and return an interned function symbol.Default to the one near point."(let*((symb(function-at-point))(enable-recursive-minibufferst)(val(completing-read(formatprompt(ifsymb(format" (default %s)"symb)""))obarray'fboundptnil'function-history)))(if(equalval"")symb(internval))));;;###autoload(defuntrace-function(function&optionalbuffer)"Traces FUNCTION with trace output going to BUFFER.For every call of FUNCTION Lisp-style trace messages that display argumentand return values will be inserted into BUFFER. This function generates thetrace advice for FUNCTION and activates it together with any other advicethere might be!! The trace BUFFER will popup whenever FUNCTION is called.Do not use this to trace functions that switch buffers or do any otherdisplay oriented stuff, use `trace-function-background' instead."(interactive(list(trace-function-read"Trace function%s: ")(read-buffer"Output to buffer: "trace-buffer)))(trace-function-internalfunctionbuffernil));;;###autoload(defuntrace-function-background(function&optionalbuffer)"Traces FUNCTION with trace output going quietly to BUFFER.For every call of FUNCTION Lisp-style trace messages that display argumentand return values will be inserted into BUFFER. This function generates thetrace advice for FUNCTION and activates it together with any other advicethere might be!! Trace output will quietly go to BUFFER without changingthe window or buffer configuration at all."(interactive(list(trace-function-read"Trace function in background%s: ")(read-buffer"Output to buffer: "trace-buffer)))(trace-function-internalfunctionbuffert))(defununtrace-function(function)"Untraces FUNCTION and possibly activates all remaining advice.Activation is performed with `ad-update', hence remaining advice will getactivated only if the advice of FUNCTION is currently active. If FUNCTIONwas not traced this is a noop."(interactive(list(ad-read-advised-function"Untrace function: "'trace-is-traced)))(cond((trace-is-tracedfunction)(ad-remove-advicefunction'aroundtrace-advice-name)(ad-updatefunction))))(defununtrace-all()"Untraces all currently traced functions."(interactive)(ad-do-advised-functions(function)(untrace-functionfunction)))(provide'trace);;; trace.el ends here